The present invention relates to a power saw with oppositely reciprocating saw blades.
The European patent document EP-A1 267311 discloses a power saw with a contour corresponding to the contour of a traditional fox-hand saw with trapezoidal saw blade. The fox-saw blade is however subdivided several times in the power saw. A trapezoidal supporting plate identified as a sword guides in its lower, groove-like region the back of the two reciprocating saw blades. The sword is composed of two trapezoidal sheet plates which are flatly mounted on one another and are laterally offset from one another so that a U-shaped groove is formed. Both saw blades are secured in this groove against falling out and guided narrowly near one another.
It has been recognized during their use that such saws have the disadvantage in the relatively high friction between the saw blades and the guide sword as well as a relatively bad chip withdrawal from the region of the cutting joint of the workpiece which is machined. This contributes to jamming of the accumulated chips in the region of the guides of the saw blades and the sword. This in turn leads to excessive warming up or overheating of the sword and the saw blades and is a cause of relatively low efficiency of the saw.
Moreover, the production of known swords is relatively expensive. The reason is that it involves different deformation and connection techniques which is of course undesirable.